This invention relates generally to computer networks and, more particularly, to techniques for configuring large interconnected networks to enable proper routing of messages to their intended destinations. The interconnection of many local area networks (LANs) and larger networks, sometimes referred to as wide area networks (WANs), is now a relatively well understood concept in most business, educational and government organizations. Computers may be interconnected through telephone lines, coaxial cables, optical fibers, radio or microwave communication links, earth-orbiting satellites, or other means.
In a large interconnected computer network, such as the Internet, computers may be categorized by the principal functions they perform. For example, there are user computers that function as network nodes or stations, sometimes referred to as host computers, which send and receive messages over a network in the form of packets of data. Other computers function as servers, and distribute requested data to network users with host computers. Computers in another category function solely to route data packets or messages from one part of the network to another. These are known by various names suggestive of the specific functions they perform, such as bridges, routers, switches and gateways. A bridge is a device that is connected to at least two LANs and serves to pass message frames or packets between the LANs, such that a source station on one LAN can transmit data to a destination station on another LAN without concern for the location of the destination. A bridge "listens" to messages from every LAN to which it is connected and relays the message onto all the other LANs to which it is connected. Routers perform an analogous function but make use of a network identifier in a message destination address to determine an optimum path for the message.
Every network station or node has both a physical address and a logical address. The physical address is a unique numerical or other code that uniquely defines the station and the local network to which it is connected. The logical address is usually a name or label associated with the station or the person using it. The logical address, which may include a person's name, is the address other users employ to direct messages to the person without having to remember or look up a long and complicated physical address.
In any large organization with many interconnected computers, whether it be a business, educational or military organization, proper routing of data messages from one network station to another depends largely on having the network accurately configured. That is to say, each network station or host must have its hardware address properly set up and each router or other message routing computer must be properly programmed to reflect exactly the physical locations of the stations in the network, the relationships between the physical and logical addresses, and the interconnection paths between all the computers and interconnected LANs in the network. This configuration process is conventionally performed manually, typically by technicians or system administrative personnel.
As interconnected networks become more complex, it also becomes more difficult to ensure that every network component has been correctly configured. The principal reason that manual network configuration is tolerated in large organizations is that in many cases the network configuration is relatively static, and the required changes are small and incremental. When a new employee joins the network or changes physical locations, it is a relatively simple matter to reconfigure the network to include his or her computer in the appropriate new location. Extensive corporate reorganizations are typically infrequent and there is usually adequate warning to make the necessary configuration changes.
A more difficult problem is presented when frequent changes are needed in the network configuration. One example is a military communication network in which many of the computer stations are mobile and reconfiguration may be needed on a daily or even more frequent basis during military maneuvers. In this case, there is simply not enough time for manual reconfiguration of a large interconnected network of computers.
Accordingly, there is a significant need for an automated process to reconfigure large computer networks, such as wireless military networks. Even in a commercial setting where there is usually enough time to reconfigure networks when changes occur, there is a need for a technique that would effect network reconfiguration more quickly and reliably than by manual means. The present invention satisfies this need and provides a number of other related advantages.